To allow transparent usage of IPv4 in IPv6 applications, scan_ip6 also understands IPv4 addresses in dotted-decimal notation and will return an IPv4-mapped IPv6 address (i.e. "127.0.0.1" will be parsed as "::FFFF:127.0.0.1".

Unlike many other IP parsing routines, scan_ip6 does not recognize octal (like 0177.0.0.1) or hexadecimal numbers (like 0x7f000001) in the IPv4 part.